Nestle Purina PetCare Company faces a lawsuit that claims its dog food, Beneful, contains toxins that are poisonous to animals. Purina says that the lawsuit is "baseless," and "we intend to vigorously defend our high quality, nutritious food."

Frank Lucido, a pet owner in California, brought a class-action lawsuit against the major dog food provider, after three of his pets became sick and one died.

He claims that his three dogs – an eight-year-old English Bulldog, a four-year-old German Shepherd, and an 11-year-old Labrador—began eating Beneful exclusively in late December or early January, and soon after became ill. The English Bulldog died, and a post-mortem examination revealed internal complications. In a veterinary exam, the other dogs showed symptoms “consistent with poisoning,” reported NBC News.

According to Mr. Lucido, the only thing the dogs had in common was their diet. Due to home renovations, each dog was living in a different location, reducing the possibility of a common environmental factor.

Mr. Cereghino said that upon researching the case, there were a number of similar incidents and complaints that had been filed against the company, many of which are shared on ConsumerAffairs.com. The site rates Beneful with one out of five stars for customer satisfaction, averaged from over 800 reviews. Complaints include pets experiencing several health issues and even death.

Are these symptoms a coincidence, or does Beneful actually contain toxic ingredients? Could the dog food have been tainted somewhere in the distribution and sale process? The lawsuit hopes to determine whether or not Purina is at fault for the illnesses allegedly occurring from their product.

A class action lawsuit was recently filed against Beneful. We believe this lawsuit to be baseless and intend to vigorously defend our high quality, nutritious food, which is backed by Purina’s strict quality controls and comprehensive food safety program. Beneful is enjoyed by millions of dogs every day and consumers can continue to feed Beneful with total confidence. We encourage you to reach us with any questions at 1-800-877-7551 or visit: http://puri.na/BenefulFAQ.

In a similar statement emailed Feb. 25 to Snopes.com, a website that investigates rumors, Purina said:

"In fact, in 2014, nearly 1.5 billion Beneful meals were served to millions of happy, healthy dogs who enjoy and thrive on this food.

"Recently, a class action lawsuit was filed against Beneful in Northern California. We believe the lawsuit is baseless, and we intend to vigorously defend ourselves and our brand. Beneful had two previous class action suits filed in recent years with similar baseless allegations, and both were dismissed by the courts. Class action suits are common in business these days. They are not indicative of a product issue."

One of the ingredients questioned by the lawsuit is the food additive propylene glycol. The additive is FDA-approved, and has not been linked to toxicity, according to the Daily Beast. Purina maintains on their website: “Propylene glycol is an FDA-approved food additive that’s also in human foods like salad dressing and cake mix.”

Another possible toxin named in the lawsuit is mycotoxins, a byproduct of mold that can be found in all types of grain. Beneful ingredients include whole wheat flour, rice flour, soy flour, and corn, leaving the possibility that mycotoxins, which can be difficult to detect, could be in the product.

Purina said in regards to the lawsuit: "Like other pet foods, Beneful is occasionally the subject of social media-driven misinformation. Online postings often contain false, unsupported and misleading allegations that cause undue concern and confusion for our Beneful customers."

Pet owners like Lucido are hopeful the lawsuit will shed some light on whether harmful ingredients are being used in the food supplied to their pets.

"Cases like these are important because we do invest so much love and time in our pets and they are such a part of our family," Cereghino told NBC News. "What is going on at this point is significant in the lives people who lost their pets."